1. Field of the Invention
Inherent or unique vibrations occur with a yarn guide disposed on a ring spinning frame when the yarn quide comes into contact with spinning yarns. This invention relates to an apparatus having a piezo-electric element disposed at a yarn guide for sensing the vibrations, a yarn guide installation lappet and electrical connections leading out the output of the piezo-electric element, for the purpose of detecting broken yarns.
2. Description of the Prior Art
In ring frames or other similar spinning machines, early inspections of yarn breaks are of great importance to increase production, minimize refused yarns and prevent failures in advance.
To this end several broken yarn detectors are well known: the photoelectric tube type whereby movements of a flier in contact with yarns due to breaks in the yarns are sensed; the dielectric constant type, etc. Those detectors are divided into two types; those wherein detectors sense yarn breaks in the progress of travelling along spinning yarn lines and those wherein the counterparts are disposed on individual spinning parts.
However, the former or moving type needs a device to move and guide the detectors and in particular substantial expenditures in applying the detectors to the conventional frames. The latter is therefore more desirable. Moreover, the above described photoelectric tube type or dielectric constant type is expensive and it is almost impractical to dispose the detectors at the individual spinning parts, from an economic point of view. There is a requirement that those detectors be disposed at the individual spinning parts and easily applicable to the conventional frames.
Conveniently, yarn guides are disposed on the ring frames for guiding spinning yarns onto bobbins and cause vibrations when coming into contact with the spinning yarns. Another approach which is well known is to sense the vibration for detecting broken yarns through the utilization of a piezo-electric element. It is also well known that the vibrations due to contact with the spinning yarns are discriminated from that accompanying mechanical vibrations of the ring frames in indicators of breaks in yarns.
Nevertheless, no system is suggested which picks up collectively the electromotive forces of piezo-electric elements disposed on a multiplicity of yarn guides and detects their unique vibrations. In addition, there is no suggestion on a specific structure of lappets for leading out signals developed from the piezo-plectric elements.